How to inset a face?
You could use the Inset tool (I):


  This tool takes the currently selected faces and creates an inset of
  them, with adjustable thickness and depth. The tool is modal, such
  that when you activate it, you may adjust the thickness with your
  mouse position. You may also adjust the depth of the inset during the
  modal operation by holding Ctrl.



Select the faces to inset:


Press I to inset: